Food preservation is an important consideration in the packaging of many food products. For example, it is often important, that for a food product which may be susceptible to spoilage through bacterial and/or mold growth, and which is intended to be consumed more than a few days after packaging, that steps be taken to inhibit microbial growth, e.g., spoilage bacteria and mold growth in the packaged product. It has long been recognized that techniques such as freezing, retort canning and preservation through the addition of chemical biostatic and fungistatic agents can, in many cases, be employed with satisfactory results.
However, as is well known, freezing requires substantially constant refrigeration from the time of packaging until the time of consumption. Further, some products do not lend themselves well to freezing without some change in the properties of the product. Further yet, required thawing of a product may be inconvenient or undesirable.
The process of retort canning involves heating of the product at the time of retort canning or packaging to destroy a significant amount of bacteria and molds in the product and, thus, render the product substantially sterile. Usually, such products are first packaged or canned, and then the container is heated to some temperature for a specified period of time. Recognized limitations of this process reside in that it is not suitable for use with products which do not tolerate these high temperatures well. For example, certain products may cook at the sterilizing temperatures. Thus, in some cases, retort canning may not be desirable for certain food products, particularly in cases in which the product is a batter, or the like, which is intended to be cooked immediately prior to consumption, for example. In other cases, it may not be desirable to cook the product at all.
As set forth, the addition of chemical additives to the product can, in some cases, be effective to inhibit the growth of the bacteria and mold. However, certain food products possess chemical properties which may be inconsistent with the conditions under which biostatic and fungistatic agents are effective. For example, it is known that certain agents work more effectively when a food product is maintained at a low pH level. However, in many cases a low pH level cannot be reasonably maintained in a food product due to inter-reaction of the ingredients of the product with acid. This is particularly true with premixed batters used to prepare baking products such as bread, biscuits, pancakes, and the like, for example. These products use a leavening agent, which generally cannot exist in a low pH solution without prematurely reacting with the acid of the solution.
For example, U.S. Pat. No. 2,810,650, issued Oct. 22, 1957, entitled “Refrigeration of Doughs and Batters Including as a Leavening Component Dicalcium Phosphate Dihydrate” (Joslin), U.S. Pat. No. 3,275,451, issued Sep. 27, 1966, entitled “Alpha-Glucoheptono Gamma-Lactone Containing Premix for Leavened Baked Food Products” (Holstein) and U.S. Pat. No. 3,170,795, issued Feb. 23, 1965, entitled “Culinary Mix for Producing Chemically Leavened Baked Goods” (Andre) disclose that leavening action results from the reaction of an acidulant in the presence of a gas-producing compound. It is also appreciated by these patents that premature leavening of such compositions is to be avoided. These patents suggest the incorporation of an acidulant whose acidity is activated by the baking temperature for reaction with the gas producing bicarbonate. The delayed acting acidulants disclosed are dicalcium phosphate dihydrate, alpha-glucoheptono-gamma-lactone and glucono-delta-lactone. U.S. Pat. No. 3,021,220, issued Feb. 13, 1962, entitled “Prepared Batters” (Going) similarly discloses that gas-producing chemical leavening agents should not be added to batters prior to the heating step, and if used, should preferably be added just prior to the baking of the batters by the ultimate consumer. U.S. Pat. No. 328,419, issued Oct. 13, 1885, entitled “Baking-Powder” (Marsh) discloses an acid lactate baking powder in which the acid and alkaline salts are protected from reaction during storage by the presence of a fatty material. U.S. Pat. No. 1,264,592, issued Apr. 30, 1918, entitled “Baking-Powder and Process of Making Same” (Atkinson) also suggests prevention of pre-reaction of baking powder by fatty separation of components.
In commercial baking, batters and doughs are often formulated by hundreds, if not thousands of pounds. As with any food product, doughs and the resulting cooked or baked goods have organoleptic properties, which are based upon the dough formula, thorough mixing, uniform distribution of dough components, and uniformity of physical properties within the dough. Uneven or a lack of full mixing may affect taste, texture, and mouthfeel of the dough, for example. Nonuniform dough mixing may also result in a variance in dough can pressure and, in turn, decreased shelf stability, and reduced performance of the eventual food product.
Another problem faced in the production or formulation of dough is that the viscoelastic properties of dough may change as the dough continues to develop and build viscosity. Minor ingredients or constituents, which are placed into the dough in smaller concentrations, often have important roles in contributing organoleptic properties to the dough. However, these same constituents are often the most difficult to mix homogeneously within the developing dough. For example, leavening agents may be incorporated in refrigerated doughs. The type, quantity, and combination of leavening agent is tailored to each product to give optimum volume, texture, performance and quality.
Typically, doughs are prepared by mixing flour, water and dough-developing agents in a first cycle. Minor ingredients, including leavening agents for example, are added to the developing dough in a second cycle. The first cycle is generally intended to provide a peak viscosity and is generally the longest period in dough mixing. The development of a peak viscosity is important to the commercial production of large volumes of doughs and baked goods.
In order to maintain the efficiency of the dough formulation process, the second cycle often takes place over a relatively shorter period of time. As a result, minor ingredients such as leaveners, flavors and nutrients may be mixed throughout the dough in a manner which is less than completely homogenous, and the dough may have uneven concentrations of leavener dispersed throughout the dough matrix.
Problems which may occur when the dough ingredients are not thoroughly mixed include less than adequate proofing and low specific volumes in final baked goods, for example. Commercial doughs are typically packaged in cans for example, so a lack of uniform mixing can result in some cans having too much leavening, and therefore an excessively high can pressure, and other cans having too little leavening, and therefore an excessively low can pressure. If the can pressure is too high the can might burst, leading to unusable product. If the can pressure is too low, the dough might not be shelf stable, and might spoil because there was insufficient pressure to expel all of the oxygen from the can. A non-uniform distribution of ingredients may also result in non-uniform final products or a final product with a lower specific volume.
To insure the even distribution of ingredients within the dough, a manufacturer may have to extend the amount of time the ingredients are mixed. This can result in an increased production time, decreased output capacity and, therefore, decreased manufacturing efficiency. Longer mixing times may also cause the dough to attain a viscosity beyond its peak viscosity, adversely affecting the dough's viscoelastic properties.
Prior disclosures concerning dough formulations include U.S. Pat. No. 3,620,763, issued Nov. 16, 1971, entitled “Refrigerated Batter Products and Method for Preparing Same” (Hans), which is directed to a ready-to-bake refrigerator dough, which exhibits stability against microbial growth. Hans teaches the addition of polysaccharide hydrophilic film formers to dough to enhance storage stability. However, Hans does not disclose a method to enhance the uniformity of the ingredients within the dough.
U.S. Pat. No. 4,022,917, issued May 10, 1977, entitled “Process for Preparing a Storage Stable Premixed Batter” (Selenke) teaches maintaining the premixed batter at an acidic pH of about 5 or less to inhibit microbial growth by isolating the acidified batter from the alkaline leavening ingredients of the mixture. To isolate the alkaline leavening agent from the acidified batter, the alkaline leavening agent is encapsulated within a water-insoluble coating that is meltable or heat-dispersible. The coating prevents the alkaline leavening agent from reacting with the acidic leavening agent in the batter until the batter is cooked. An acidic environment inhibits bacterial growth and can enhance the activity of some fungistatic agents. However, Selenke teaches the use of very large microspheres containing sodium bicarbonate. Such capsule sizes may tend to leave brown spots on dough and a poor appearance. In addition, the large size of the microspheres may tend to lead to uneven leavening during the cooking process. Further, many food approved coating materials used in sodium bicarbonate microspheres may tend to develop micro fissures, cracks or to dissolve when stored in the acidified batter over time, causing premature reaction and negating the antimicrobial or fungicidal function of the acid in the batter.
U.S. Pat. No. 5,409,720, issued Apr. 25, 1995, entitled “Room-Temperature Shelf-Stable Dough Mix” (Kent) teaches a dough mix including a moist ingredient portion and a dry ingredient portion capable of being combined to produce complete dough requiring no additional ingredients. The moist ingredient portion includes sugar, shortening and the water or moisture required in the complete dough. The dry ingredient portion includes the flour required in the complete dough and may include leavening agents, egg solids, candy pieces, nuts, dried fruits, coconuts and other dry or moisture-free ingredients. Kent is directed to a method for adding compatible ingredients, but does not offer a totally self-contained shelf stable batter product.
U.S. Pat. No. 5,855,945, issued Jan. 5, 1999, entitled “Method of Preparing Dough” (Laughlin) teaches a means of forming pre-mixed dough whereupon an encapsulated leavening agent is employed in the formulation.
None of these known methods insure that the dough product will have an adequately mixed and shelf stable leavening system though. The use of sodium bicarbonate in an encapsulated form relies upon a capsule shell composed of fats, waxes or hydrogenated vegetable oils. These fats may have acid soluble functional groups. Immersing the encapsulated sodium bicarbonate made from such shell materials may result in low shelf life, as the liquid batter is acidic, kept at a pH of 5.0 to 5.5 for example. At such a range fats, hydrogenated vegetable oils and food approved waxes may tend to slowly disintegrate over time, eventually enabling the acidulant and the bicarbonate to come into direct contact, usually far before the shelf life desired period is reached. The acidic environment of the batter, used to keep microbial growth to a minimum during storage and to affect the chemical leavening reaction during baking, may also cause deterioration of the capsule shell materials used to form encapsulated bicarbonates. This leads to a short shelf life as premature reaction forms carbon dioxide gas and swells the container in which the liquid batter is stored. The premature reaction also minimizes the leavening effect upon baking and can reduce the effectiveness of the batter to act as an antimicrobial composition as the acidulant loses its potency.
As a result, products produced by the methods described above may not be uniform, due to uneven leavening action, suffer a short shelf life, and/or result in a baked good or dough product with poor appearance, uneven shape and/or a poor taste profile.